The Experts below are selected from a list of 144 Experts worldwide ranked by ideXlab platform
A. Méndez - One of the best experts on this subject based on the ideXlab platform.
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choice of pyrolysis parameters for urban wastes affects Soil enzymes and plant germination in a Mediterranean Soil
Science of The Total Environment, 2018Co-Authors: I Benavente, Jorge Pazferreiro, Gabriel Gascó, Cesar Plaza, A. MéndezAbstract:The production of organic waste has steadily increased in recent years, with subsequent impact on the environment. The European Union committed to diminish the volume of biodegradable municipal waste disposed of in landfills by 2016-2020. The synthesis of biochar from urban waste and its application to improve Soil quality can constitute a novel route for valorization. The aim of this paper was to study the effect of three biochars originated from pyrolysis of the organic fraction of urban waste at two different temperatures (300°C and 500°C) and two residence times (1h and 5h) on the biochemical properties of an agricultural Soil. Soil was amended with biochars at a rate of 8% and incubated for 74days. A phytotoxicity assay, using garden cress as the test species, was conducted. CO2 emissions, microbial biomass C and the enzymes dehydrogenase, phosphomonoesterase and β-glucosidase were measured in tested Soils. Biochars prepared at 300°C resulted in lower germination index values, which could partly be ascribed to a higher bioavailability of heavy metals and higher soluble organic matter, while the biochar prepared as 500°C exhibited a phytostimulant effect. Biochars produced at 300°C (B300-1h, B300-5h) augmented Soil CO2 emissions while there was no effect on microbial respiration in the Soil amended with the biochar prepared at 500°C. Pyrolysis temperature and, for some enzymes, residence time, controlled Soil enzymatic activity.
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Effects of sewage sludge biochar on plant metal availability after application to a Mediterranean Soil.
Chemosphere, 2012Co-Authors: A. Méndez, Jorge Paz-ferreiro, Amaia Gómez, Gabriel GascóAbstract:Pyrolytic conversion of sewage sludge into biochar could be a sustainable management option for Mediterranean agricultural Soils. The aim of this work is to evaluate the effects of biochar from sewage sludge pyrolysis on Soil properties; heavy metals solubility and bioavailability in a Mediterranean agricultural Soil and compared with those of raw sewage sludge. Biochar (B) was prepared by pyrolysis of selected sewage sludge (SL) at 500°C. The pyrolysis process decreased the plant-available of Cu, Ni, Zn and Pb, the mobile forms of Cu, Ni, Zn, Cd and Pb and also the risk of leaching of Cu, Ni, Zn and Cd. A selected Mediterranean Soil was amended with SL and B at two different rates in mass: 4% and 8%. The incubation experiment (200 d) was conducted in order to study carbon mineralization and trace metal solubility and bioavailability of these treatments. Both types of amendments increased Soil respiration with respect to the control Soil. The increase was lower in the case of B than when SL was directly added. Metals mobility was studied in Soil after the incubation and it can be established that the risk of leaching of Cu, Ni and Zn were lower in the Soil treated with biochar that in sewage sludge treatment. Biochar amended samples also reduced plant availability of Ni, Zn, Cd and Pb when compared to sewage sludge amended samples.
Gabriel Gascó - One of the best experts on this subject based on the ideXlab platform.
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choice of pyrolysis parameters for urban wastes affects Soil enzymes and plant germination in a Mediterranean Soil
Science of The Total Environment, 2018Co-Authors: I Benavente, Jorge Pazferreiro, Gabriel Gascó, Cesar Plaza, A. MéndezAbstract:The production of organic waste has steadily increased in recent years, with subsequent impact on the environment. The European Union committed to diminish the volume of biodegradable municipal waste disposed of in landfills by 2016-2020. The synthesis of biochar from urban waste and its application to improve Soil quality can constitute a novel route for valorization. The aim of this paper was to study the effect of three biochars originated from pyrolysis of the organic fraction of urban waste at two different temperatures (300°C and 500°C) and two residence times (1h and 5h) on the biochemical properties of an agricultural Soil. Soil was amended with biochars at a rate of 8% and incubated for 74days. A phytotoxicity assay, using garden cress as the test species, was conducted. CO2 emissions, microbial biomass C and the enzymes dehydrogenase, phosphomonoesterase and β-glucosidase were measured in tested Soils. Biochars prepared at 300°C resulted in lower germination index values, which could partly be ascribed to a higher bioavailability of heavy metals and higher soluble organic matter, while the biochar prepared as 500°C exhibited a phytostimulant effect. Biochars produced at 300°C (B300-1h, B300-5h) augmented Soil CO2 emissions while there was no effect on microbial respiration in the Soil amended with the biochar prepared at 500°C. Pyrolysis temperature and, for some enzymes, residence time, controlled Soil enzymatic activity.
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Effects of sewage sludge biochar on plant metal availability after application to a Mediterranean Soil.
Chemosphere, 2012Co-Authors: A. Méndez, Jorge Paz-ferreiro, Amaia Gómez, Gabriel GascóAbstract:Pyrolytic conversion of sewage sludge into biochar could be a sustainable management option for Mediterranean agricultural Soils. The aim of this work is to evaluate the effects of biochar from sewage sludge pyrolysis on Soil properties; heavy metals solubility and bioavailability in a Mediterranean agricultural Soil and compared with those of raw sewage sludge. Biochar (B) was prepared by pyrolysis of selected sewage sludge (SL) at 500°C. The pyrolysis process decreased the plant-available of Cu, Ni, Zn and Pb, the mobile forms of Cu, Ni, Zn, Cd and Pb and also the risk of leaching of Cu, Ni, Zn and Cd. A selected Mediterranean Soil was amended with SL and B at two different rates in mass: 4% and 8%. The incubation experiment (200 d) was conducted in order to study carbon mineralization and trace metal solubility and bioavailability of these treatments. Both types of amendments increased Soil respiration with respect to the control Soil. The increase was lower in the case of B than when SL was directly added. Metals mobility was studied in Soil after the incubation and it can be established that the risk of leaching of Cu, Ni and Zn were lower in the Soil treated with biochar that in sewage sludge treatment. Biochar amended samples also reduced plant availability of Ni, Zn, Cd and Pb when compared to sewage sludge amended samples.
Cesar Plaza - One of the best experts on this subject based on the ideXlab platform.
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choice of pyrolysis parameters for urban wastes affects Soil enzymes and plant germination in a Mediterranean Soil
Science of The Total Environment, 2018Co-Authors: I Benavente, Jorge Pazferreiro, Gabriel Gascó, Cesar Plaza, A. MéndezAbstract:The production of organic waste has steadily increased in recent years, with subsequent impact on the environment. The European Union committed to diminish the volume of biodegradable municipal waste disposed of in landfills by 2016-2020. The synthesis of biochar from urban waste and its application to improve Soil quality can constitute a novel route for valorization. The aim of this paper was to study the effect of three biochars originated from pyrolysis of the organic fraction of urban waste at two different temperatures (300°C and 500°C) and two residence times (1h and 5h) on the biochemical properties of an agricultural Soil. Soil was amended with biochars at a rate of 8% and incubated for 74days. A phytotoxicity assay, using garden cress as the test species, was conducted. CO2 emissions, microbial biomass C and the enzymes dehydrogenase, phosphomonoesterase and β-glucosidase were measured in tested Soils. Biochars prepared at 300°C resulted in lower germination index values, which could partly be ascribed to a higher bioavailability of heavy metals and higher soluble organic matter, while the biochar prepared as 500°C exhibited a phytostimulant effect. Biochars produced at 300°C (B300-1h, B300-5h) augmented Soil CO2 emissions while there was no effect on microbial respiration in the Soil amended with the biochar prepared at 500°C. Pyrolysis temperature and, for some enzymes, residence time, controlled Soil enzymatic activity.
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biochemical properties and barley yield in a semiarid Mediterranean Soil amended with two kinds of sewage sludge
Applied Soil Ecology, 2009Co-Authors: Jose Garcia M Fernandez, Cesar Plaza, Juan Carlos Garciagil, Alfredo PoloAbstract:Abstract Recycling sewage sludges as Soil organic amendment and as a source of macro- and micronutrients represents a promising agricultural practice, especially in Mediterranean areas, where Soils commonly exhibit low organic matter contents. However, this organic waste must be treated to avoid potential hazardous effects over the Soil or the plants. For this aim, there are different treatments, some of them of contrasted feasibility, such as composting. However, the implementation of recent technologies, like thermal-drying, allows obtaining in less time a final product with exceptional handling conditions. This modern treatment has been introduced in an increasing number of wastewater treatment plants during the last years. Nevertheless, the effects of thermally dried sewage sludge on Soil biota and crop yields have not been widely studied to date. In this work, composted and thermally dried sewage sludges were applied to a cropped Soil over a three-year period, with different frequencies (single or yearly applications) and at two rates (20 and 80 t ha−1), to investigate and compare their cumulative and residual effects on the yield of barley and on chemical, biological and biochemical Soil properties. In the cumulative experiment high doses of both sewage sludges caused an increase of the total organic C contents but also a significant decrease in crop yield, as well as in enzyme activities and microbial biomass C contents. In contrast, cumulative applications of both types of sewage sludge at low doses showed, in general, better barley yield parameters as well as significantly higher microbial biomass C contents, particularly for the composted one. The best results for barley yield were obtained in Soils amended once with sewage sludge, particularly for those amended with the composted sewage sludge. These results may be attributed to a possible deleterious effect over Soil properties derived from the use of excessive doses. Besides, the results stood out the benefits derived from the application to Soil of the composted sewage sludge, which presented a much more mature and stable organic matter than the thermally dried sewage sludge.
Simon Navarro - One of the best experts on this subject based on the ideXlab platform.
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solarization based pesticide degradation results in decreased activity and biomass of the Soil microbial community
Geoderma, 2019Co-Authors: M Diazlopez, C Garcia, Nuria Vela, Simon Navarro, I Garrido, E Nicolas, J Fenoll, Felipe BastidaAbstract:Abstract Pesticides are chemical compounds, mostly synthetic, which are used widely in agricultural fields to prevent and to control pests and Soil-borne diseases. The synthetic nature of these compounds makes some of them non-biodegradable and they may accumulate in harmful concentrations in Soils. Solarization seems to be a non-chemical strategy that could enhance pesticide degradation in Soils. Here, we evaluate the combined impact of pesticides and solarization on the microbial community of a Mediterranean Soil. For this purpose, enzyme activities, basal respiration, and the biomass and composition of the microbial community (through analysis of phospholipid fatty acids, PLFAs) were evaluated in solarized and non-solarized Soils, in a 90-day greenhouse experiment with a combination of different pesticides. The degradation of the pesticides in the solarized Soils was 30% greater than in non-solarized samples. However, solarization also affected the Soil microbial community. The Soil respiration was lowest in solarized samples without pesticides, while the enzyme activities were greater in non-solarized samples (with and without pesticides). Both the bacterial and fungal PLFA contents declined in solarized samples. The G+/G− ratio was highest in the solarized samples without pesticides and in the non-solarized samples with pesticides. Considering such impacts on the Soil microbial community and the relationship of Soil microbes with Soil ecosystem services, the utilization of solarization must be carefully considered when adopting strategies for pesticide degradation in Mediterranean Soils.
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trial of solar heating methods solarization and biosolarization to reduce persistence of neonicotinoid and diamide insecticides in a semiarid Mediterranean Soil
Science of The Total Environment, 2017Co-Authors: Nuria Vela, Jose Fenoll, G Navarro, Isabel Garrido, Simon NavarroAbstract:This paper reports the use of solar heating techniques, solarization (S) and biosolarization (BS) as a strategy for the environmental restoration of Soils containing neonicotinoid, acetamiprid (AC), imidacloprid (IM) and thiamethoxam (TH), and diamide, chlorantraniliprole (CL) and flubendiamide (FB) insecticide residues. For this, a semiarid Mediterranean Soil (Haplic calcisol) was covered with low-density polyethylene (LDPE) during the hot season, to raise the maximal Soil temperatures. Compost from sheep manure (CSM), meat-processing waste (MPW) and sugar beet vinasse (SBV) were used as organic wastes. The results showed that both S and BS increase insecticide disappearance rates compared with the non-disinfected Soil, the increase in Soil temperature and added organic matter playing a key role. The dissipation rates of TH and AC in Soil were satisfactorily described by first-order (monophasic) kinetics, while IM, CL and FB showed a deviation from exponential behaviour. For them, the best results were obtained applying biphasic kinetics with a rapid initial degradation followed by a slower decline of their residues. The findings suggest that S and BS (especially using MPW) can be considered as a valuable tool for enhancing the detoxification of Soils polluted with these insecticides.
Nuria Vela - One of the best experts on this subject based on the ideXlab platform.
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solarization based pesticide degradation results in decreased activity and biomass of the Soil microbial community
Geoderma, 2019Co-Authors: M Diazlopez, C Garcia, Nuria Vela, Simon Navarro, I Garrido, E Nicolas, J Fenoll, Felipe BastidaAbstract:Abstract Pesticides are chemical compounds, mostly synthetic, which are used widely in agricultural fields to prevent and to control pests and Soil-borne diseases. The synthetic nature of these compounds makes some of them non-biodegradable and they may accumulate in harmful concentrations in Soils. Solarization seems to be a non-chemical strategy that could enhance pesticide degradation in Soils. Here, we evaluate the combined impact of pesticides and solarization on the microbial community of a Mediterranean Soil. For this purpose, enzyme activities, basal respiration, and the biomass and composition of the microbial community (through analysis of phospholipid fatty acids, PLFAs) were evaluated in solarized and non-solarized Soils, in a 90-day greenhouse experiment with a combination of different pesticides. The degradation of the pesticides in the solarized Soils was 30% greater than in non-solarized samples. However, solarization also affected the Soil microbial community. The Soil respiration was lowest in solarized samples without pesticides, while the enzyme activities were greater in non-solarized samples (with and without pesticides). Both the bacterial and fungal PLFA contents declined in solarized samples. The G+/G− ratio was highest in the solarized samples without pesticides and in the non-solarized samples with pesticides. Considering such impacts on the Soil microbial community and the relationship of Soil microbes with Soil ecosystem services, the utilization of solarization must be carefully considered when adopting strategies for pesticide degradation in Mediterranean Soils.
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trial of solar heating methods solarization and biosolarization to reduce persistence of neonicotinoid and diamide insecticides in a semiarid Mediterranean Soil
Science of The Total Environment, 2017Co-Authors: Nuria Vela, Jose Fenoll, G Navarro, Isabel Garrido, Simon NavarroAbstract:This paper reports the use of solar heating techniques, solarization (S) and biosolarization (BS) as a strategy for the environmental restoration of Soils containing neonicotinoid, acetamiprid (AC), imidacloprid (IM) and thiamethoxam (TH), and diamide, chlorantraniliprole (CL) and flubendiamide (FB) insecticide residues. For this, a semiarid Mediterranean Soil (Haplic calcisol) was covered with low-density polyethylene (LDPE) during the hot season, to raise the maximal Soil temperatures. Compost from sheep manure (CSM), meat-processing waste (MPW) and sugar beet vinasse (SBV) were used as organic wastes. The results showed that both S and BS increase insecticide disappearance rates compared with the non-disinfected Soil, the increase in Soil temperature and added organic matter playing a key role. The dissipation rates of TH and AC in Soil were satisfactorily described by first-order (monophasic) kinetics, while IM, CL and FB showed a deviation from exponential behaviour. For them, the best results were obtained applying biphasic kinetics with a rapid initial degradation followed by a slower decline of their residues. The findings suggest that S and BS (especially using MPW) can be considered as a valuable tool for enhancing the detoxification of Soils polluted with these insecticides.